The aim of the investigations was to assess the influence of supplementation of cow rations with zinc, copper and manganese given in the form of bioplexes during the perinatal period. Colostrum ąuality and immunoglobulin level in calf serum were evaluated. Total protein and its fractions in colostrum from the first milk as well as in calves' blood serum from the 2^nd and 35^th day of life were determined. Additionally, the total immunoglobulin index in week 3-4 of life (IIg_3-4) was calculated. All calves were well supplied with colostral lactoimmunoglobulin. The highest level of γ-globulin (12.5 g/L) was found in group III and resulted from the higher level of this fraction in colostrum (93.6 g/L). The value of IIg_3-4 – 0.54 found in III group confirms that the newborn calves are well protected by colostrum.